Daemonium Pacisor Mercy
by Aureux
Summary: In a world where demon summoning has become common practice after the finding of a method that doesn't require a sacrifice or selling of a soul, Reborn finds himself contracting what may just be one of the world's weakest demons. Or is he? All!27 (Open Pairing) Demon!Tsuna (Lapse 2 now up)
1. Original Sin

**Original Sin**

* * *

" _All humans are born into the world with sinful natures, due to the sin of Adam. To be born with the sins of those before them, means that even the most innocent of babies are not truly pure. That is the nature of Original Sin. And that is the proof that all of humanity is set up to fail at maintaining any semblance of purity."_

* * *

 _Reborn's brow wrinkled in annoyance as he looked down at the figure in the circle. Why Reborn made a bet with Verde he would never know. Meanwhile golden eyes stared brightly back up at him, white teeth flashing as the demon yawned. But Reborn could only bring himself to let out a sigh and move to grab his now cool espresso._

 _See, it all had started when Verde went looking for a subject to help him with an experiment. This experiment had to do with demons. Yes, the supernatural kind. Yes, the kind from hell. Why? Well a handful of years ago demon summoning decided to spring up out of the underground societies and become a common occurrence. It all started when someone learned how to summon and contract demons without the typical selling your soul clause. This new revolutionary method became widespread and demons themselves were now common sights working behind the scenes in many aspects of life._

 _Now Verde had wanted to get his hands on one for a while, but the other Arcobaleno managed to keep him busy enough to avoid it. After all, their group contracting a demon would bring them into an unwanted line of question. His leader on the other hand had little problems with it. Her idea of mutual understanding and compassion tended to lead to such wishful thoughts. The others though… not so much._

 _But, after getting his hands on a scroll to summon a powerful one, well Verde couldn't help himself. That is where the guinea pig came in. See, he could very well accurately study the mechanics of the summoning and contracting process if he was busy doing it, could he? And so this was where the bet came in._

 _The bet was simple and almost childish in complexity. What it was about? Well… it particularly involved a speed shooting contest between Reborn and one of Verde's robots. And Reborn went drinking the night before (Reborn was an arrogant sort after all)… And well one could guess what happened. Trying to out shoot a custom build robot all the while sporting a hangover wasn't on the list of Reborn's best moments._

 _So now here he was staring at the so called "powerful" demon in the form of a 14 year old. His hair was a burnt chocolate color, eyes a bright golden honey, and clinging to his features was the smallest amount of baby fat. The only things about him that marked him as indeed being a demon was the unnatural vivid shade of his eyes and the small horns that curled just barely visible over his ears._

 _And to make matters worse, Reborn was acutely aware of the camera pointed toward the two, the annoying scientist on the other side of it surely taking down note after note with keen interest. Reborn, among arrogant and manipulative, was also a proud man. For a proud man such as he to have summoned such a weak-looking child as a demon it was naturally said pride was a little hurt._

" _Sooo what do you want? Money? Fame? Sex? Immortality? I've heard it all," the demon spoke, blocking a yawn with a raised fist. Reborn merely stared, his tired brain slowly processing what he should tell the demon among the prominent haze of his growing ire. Said ire only spiked further upon the creature's next words._

" _Against common belief, demons do actually sleep. So if you are just going to sit there staring at me, I'd rather you just dismiss me," The demon broke the silence, its eyes gaining an orange tint as it glared at the hitman with slight annoyance touching its face._

" _I don't want anything in particular. The real question is, what do you want?"_

" _What do I want?" Suddenly the cold angered expression snapped off its face, leaving behind a distant, almost innocent curiosity. That was until it was engulf a split second later by a deep boredom. "Well right now I want to sleep,"_

" _You know what I mean," the hitman clinched his hands into his pockets, resisting the urge to blow up on the demon who simply sat there blinking up at Reborn as if Reborn wasn't the man in charge here, or the one with the weapon._

" _Oooh that. I don't know,"_

 _A vein popped on Reborn's forehead and he couldn't help himself anymore. With zero effort, he rose his gun and took aim, emptying his clip into the demon._

"So yeah, he kept on shooting, getting even angrier that his bullets weren't killing me. After he finished, we settled on an agreement. In exchange for me serving him, he will…"

The demon tilted his head cutely as amusement flashed in his eyes. Around him sat his guardians, each hanging onto every word that fell from his lips. Of course there were some unsure about what the demon said, what with the fact that he had no reason to take the contract. Of course that was remedied by a few words. Yet before the conversation could reach another peek, the faint mark of a contract in the making on his collarbone silenced everyone around him.

"Well that's my cue. I'll finish my story next time I get to come back. Who knows though, maybe this will be really fun," the boy said with a childish smile on his face as he began to vanish to various calls of goodbye, the loudest being a 'Come back safe, Juudiame!'

 _Reborn was going to have his hands full. Not only did he contract just any demon, but rather he contracted the Tenth Heir to hell, Mercy._

 _Reborn's life would never be the same again._

* * *

Author's Note!:

I preformed some edits to the first chapter. Going through it, I decided to blend some and change some details that I threw in before hand without thinking that may end up being contradicted further on in the story. Those were the product of a degree of carelessness and have further been disputed.

Also I have a little treat for you all. Since I am too lazy to try and describe the seal, I just took an hour and quickly designed it.

(See cover art)

Just a little heads up. I feed on reviews. The more you review, the faster this will be updated. I plan on getting back into the swing of writing my stories, so the reviews I get will factor into that which I update first.

Also another heads up. While I personally consider the content to be teen, some may disagree. So for those who are a little shaky I will tell you here that the worst of the content will simply be coarse and colorful language. This is from Reborn's point of view and I highly doubt he has a child friendly mind, let alone tongue. You've been warned.


	2. Lapse 1

**Lapse 1**

* * *

" _While a lapse in judgement itself is often harmless, a simple mistake if you will, it often birthed from it are far grander sins."_

* * *

Reborn sat, face propped against the table in front of him and fingers clutching the coffee mug as a lifeline while Verde continued to ramble to himself about various scientific mumbo-jumbo pertaining to demon summoning. He didn't need to know about what body-part glowed when during the process and he didn't care about the power released when the portal opened. All he cared about was getting Verde to shut up because it was way too goddamn early for this shit.

"So whatcha doing?"

The voice close to Reborn's ear resulted in a twitch of epic proportions and a growing desire to just pull his gun on everybody near him, Luce's punishment be damned. Not only did he have to contract a demon, but he couldn't get rid of it. Not until the time in which the contract ended.

Now the demon would occasionally disappear from time to time, but he couldn't stay gone for long periods of time. It was as per some obscure set of laws set forth for demons. When Reborn made the mistake of trying to question further, all he received for his trouble was a yawn and a careless, "You don't need to know the specifics." From there, the hitman learned one of the first things about his demon. It was elusive when it came to questions it didn't want to or feel like answering.

"Resisting the urge to blow your brains out.."

"Well that doesn't sound very nice…"

"I never said I was nice,"

All Reborn got for his comment was a pout-like frown on its face.

"I didn't ask to summon you, so I'd appreciate it if you try to not make me contemplate homicide anymore than I already do,"

"Well you summoned me, whether you wanted to or not. Not only that, but you went through with the contract, so you are stuck with me. And hey! I haven't even done anything to warrant the threat!" The demon finally cried out indignance, face contorting into an expression like a kicked puppy that was almost too cute for it's own good..

 _Wait! I'm a goddamn hitman for Christ's sake. I don't think of anything as cute!_ Reborn lamented with a grimace as his eyes roved over the demon. Last night it was far too dark and he was long exhausted by the time the demon came, resulting in him letting loose a good two rounds into the demon. But now, in the bright fluorescence of Verde's lab he could truly get a good look.

Two golden honey eyes sat under soft spiky brown bangs, only for the hair to swoop away and up, sticking suspended as if kept in place by countless bottles of hairspray. Two thin black horns curled from the tops of its pointed ears, only to twist back and down for the tips to practically meet near the base of its skull. Its frame was small and thin, packed with lean muscle hidden by the simply chained black cargo pants and pale orange button down. A few buttons in it was left free to expose the very same contract brand that Reborn had resting on his left hip nestled on the juncture of its neck and collarbone. All in all, the demon looked just a few shades closer to cute than handsome, but with some redeeming hot qualities.

No sooner did Reborn finish cataloging the demon did the demon notice the stares, particularly at its inhuman features, and move to conceal them with whatever unholy illusion it conjured up. Even after the illusion settled itself in place, it still looked like a 14 year old boy only without the horns, the pointed ear, and eyes that now were a few shades closer to pure hazel.

"Better?"

"I wasn't complaining in the first place," Reborn rebutted.

"Well either way it was only a matter of time before I had to blend i-EEK!" The demon squeaked at Verde stuck it without a needle without warning, drawing blood from it to do whatever it is that Verde does. But the very reaction from the demon itself made Reborn struggle to hold back a chuckle. As soon as the surprise faded, the demon's eyes sharpened and it began to glare wholeheartedly at Verde. There was almost something scary about it, which made the situation all the more amusing. Who wouldn't find the humor in a teenage demon giving the scientist the stinkeye.

"Well thats my cue Verde. You can play with it later. Right now I should go ahead and inform Luce I have a demon staying with me. As amusing as I'd like to see her try and kill it, there would be a big mess left after,"

With that the hitman rose up with a grace born of constant training, and took to the stairs without another word. He didn't even truly see the point in telling the demon to follow him, supposing it would just go ahead anyway. And sure enough, it did.

"I'm not an it…" the demon mumbled, "I'm a **HE**. A male,"

"So what's your name 'He',"

"I go by many names. You can call me Mercy. Or if you can come up with a better one that that, be my guest," suddenly all the hostility drained out of it, erm him, as though that simple implication that Reborn would refer to him as a 'he' instead of an 'it' made everything better. But of all names, to call a demon Mercy was perhaps the most ironic of any.

"Okay 'Mercy', I'm Reborn. Now that that is out of the way, before we go meet my friends I have to lay down a few ground rules,"

Suddenly the larger shape turned to block the small one's path. Two onyx eyes peered out from the shadow of the fedora as a grand killing intent was released as if to threaten the demon. Funny enough, despite Mercy's weak appearance, he seemed hardly fazed.

"Let me guess. No killing anyone without your permission and other things of that nature? I'm a bit different than some of the demons you have encountered before, Hunter,"

Reborn's eyes narrowed at that comment.

"How did you know I was a Hunter?"

"I'm not stupid. I could smell the magic in your veins. All Hunter's get inoculated against any diseases they could possibly get from coming into contact with feral demons. While I guess normal human's probably could get it too, you also have some special anti-possession charms set on you. I doubt any regular human would have those," Mercy rattled off, his appearance still oddly relaxed despite identifying the human who contracted him as a someone who Hunted his kind.

"You are oddly calm for just learning the person who contracted you is your mortal enemy,"

"For one, the contract is only partial at the moment. For two, no you aren't,"

Those few words stunned Reborn.

"If memory serves me, Satan allows hunters to continue their work so long as they only target feral demons. They can't hunt and kill demons who haven't done anything. That was part of the pact that was made to allow humans to continue having access to the summoning without risking their souls," Mercy finished with hardly a change in expression. Meanwhile Reborn for once found himself wondering just who this demon was. What he just recited wasn't exactly common knowledge. So how on earth did this lowly demon know? And for another, what did he mean by the contract not being complete.

"Partial contract?"

"That is all you got from that or all you are deciding to acknowledge? Either way, for a Hunter, you are very ignorant on the matter of Contracting. I thought your order required you to know every aspect of human and demon interaction. No matter. You'll figure it out later. So, can we go now?" The voice echoed with slightly amusement as orange flickered in those honey depths, reminding the hitman/hunter just exactly where he was and what he was coming to do. Without wasting another moment, the raven-haired man pushed his way through the nearby door that lead into the dining room and right into the table of four currently indulging themselves in breakfast.

"Oh good morning Reborn. You're running later than usual. Did something come up?" A woman with dark blue-green hair that was practically black asked, lips quirked up into a kindly smile.

"Chaos, Luce. That is what I was coming to talk about. I'm sure you are aware of the bet and the results of it,"

"Why in fact I am. So you came to introduce you demon?"

Reborn responded with a slight nod of his head, before he quickly stepped out of the doorway to reveal Mercy. Mercy, who rather than lung or scheme or anything that any other demon he ever met did, simply smiled politely and bowed.

" _ **Greetings. My name at the moment is Mercy, 10th Son of Satan and heir to the throne. It is a pleasure to make your acquaintance,"**_

 _-Ten Hours Later-_

Mercy couldn't help but grumble as he sat in the passenger seat of the car. Though he was completely serious, Reborn hadn't believe his introduction. Even the woman of the house suppressed a chuckle and called him cute in response to his words. He wasn't cute or weak or whatever it was those humans thought he was. It wasn't his fault he was the youngest and it showed in his human form! He was to be the next Satan!

Or well when Father decided to go on vacation again… despite his desire not to be…

Perhaps it had to deal with his mixed blood, like his eldest brother Giotto. Both of them were outliers out of all the siblings. Their mother, unlike the demon mothers their other siblings had, was a fallen angel. Maybe it had to do with the angel bloodline, however corrupt it was, that made those two the most level headed and least bloodthirsty. Timoteo and Daniela weren't **too** bad, but they had their moments. Those moments far more frequent than Giotto or Mercy.

The young demon popped his neck as he stretched only to settle back into his seat. He could do patience, yes, but he was already in a bit of a bad mood being teased by Reborn. Even after he claimed he wasn't lying, the hitman continued to patronize him. But his impatience wasn't from anything. No it was because Reborn got a call from a job and dragged Mercy along. With this surely Mercy could demonstrate that he isn't a simple weakling no matter how he may appear.

"How much longer?"

"However much longer it takes. Now keep quiet, or I will shoot you,"

Now, while that seemed harsh, in Reborn's defence this wasn't the first time Mercy asked that question. Actually more like closer to the 15th time.

"Why do we have to stake this place out anyway? We already know the demon is in there,"

"Because if we run right in while there may be a chance of bystanders, then they may get hurt too,"

"So what?"

 _Bang._ A perfect hole erupted from Mercy's thigh, logging itself in the meat and prompting a hiss from the young demon.

"Your kind may do things differently, but we humans value the lives of innocents," The hitman spat, his killing intent spreading through the car so tangible it was near suffocating.

"Well sorry for asking…" Mercy mumble back. He himself wasn't exactly sure what he did wrong. It may have not been a common occurrence for him to interact with humans (well he did interact with one in the past fifty years, but that man hardly counted as a regular human in his book). And as much as it stung like an insult, Reborn was right. His kind could care less about innocents. If a weaker demon got in the way of stronger ones by pure accident they would simply be ignored and likely killed without a second thought. His world wasn't exactly one of Mercy, which made his name all the more interesting.

He would never admit to someone who didn't know that it fit him perfectly.

In Hell, the weak would be killed and devoured. His mercy and kindness was one such weakness. So Mercy kept that side of him locked up, only free for his friends to see. While he managed to get Mukuro to join him it was only because the man was once a human who turned into a demon due to the strong negative emotions he experienced upon being tortured and experimented on before death.

Even among his only family, there were just a few who wouldn't ridicule him for his softer side. Timoteo, Giotto, Daniela, and, oddly enough, his father himself saw no problems with it. If anything they encouraged it. According to Giotto, it was because the two of them were a of a pure and gentle darkness that didn't suffocate but rather encompassed in a way similar to light. For those who truly needed it, they drew in people like a beacon and were like a breath of fresh air in the otherwise hostile place.

Outside of his family, his guardians, and Giotto's guardians, there was only one other attracted to that light. A kind of shinigami of sorts who policed both the true Underworld and Earth's version of such. But it had been a while since the two interacted.

A gasp of breath brought the demon out of his thoughts as his healing factor activated and with a contraction of muscles what was left of the bullet was pushed out with a small amount of silver blood. Luckily, or unluckily since it could have easily proved Mercy true, his blood began to smoke and bubble soon after. (Demon's bodies reflect heat like a mirror reflects light. The heat increases exponentially when regeneration occurs. It doesn't help that Mercy is a fire-based demon. Luckily his outermost skin is like a rubber protector so he doesn't burn his clothes or melt things around him. But under his skin mixture with regeneration it easily reaches around 100 degrees celsius.)

Rather than react to the sight, Reborn simply pushed open his door.

"It's time."

 **Omake! Reborn's Demon Discussion Corner!**

Reborn pulled out a pointer from his pocket and turned to the chalkboard in front of the classroom.

"Chaos. Today we will introduce the demon ranking system. There are Four Tiers.

"In the First is Satan and his Four generals. Each general is both a guardian of one of the cardinal directions in Hell, as well as a Horseman of the Apocalypse. They can be identified by their ability to appear as beautiful humans without any sign of being a demon. But, they can be recognized. If made to bleed, their blood can be observed to be of a golden color. Sadly the chances of making one of them bleed is a million and one.

"In the Second are the Ten Kings of Hell, all of which is directly sired by Satan himself. (There are some rumors about a secret 11th Court, though nothing has been confirmed.) Each of the King's have anywhere from 7 to 13 guardians. Those guardians act as their closest advisors. While their human forms are always without perfection, they can blend in quite easily. They just look more like common-pretty humans rather than the 'supermodel' forms of the First Tier. Their blood is a vibrant silver if shed.

"In the Third are the Guards or Courts of the Kings of Hell. Each King has roughly 7 to 13 of them. Some of this rank can also exist outside of the Courts, but it is rare. Their human forms always have some kind of feature that hints at their true nature, whether it be an extra eyes, a tail, or maybe unnatural ears. Their blood is pitch black and said not to reflect any light.

"In the Four we come in with the common demons. These demons cannot take human form on their own and usually have to turn to possessing people in order to blend in among humans. Their blood is a snot green.

"While the first three tiers are the most powerful, they are also the most reasonable and intelligent. While the fourth is the easiest to contract and control, they are also the most likely to become hostile and go on rampages. In some cases the third tier has been known to take contracts with permission from their king's, but it is next to unheard of for a second rank to have a contract with a human. This is the exactly reason why I say that Mercy cannot be in the Third Rank… even though his human form is next to flawless… Maybe he is hiding a tail in his pants or something.

Anyway that is the end of the lesson. Now get out of here before I shoot you."

* * *

Author's Note!:

I preformed some edits to the second and third chapter as well as to blend the two together. Going through it, I decided to change some details that I threw in before hand without thinking that may end up being contradicted further on in the story. Those were the product of a degree of carelessness and have further been disputed.

Just a little heads up. I feed on reviews. The more you review, the faster this will be updated. I plan on getting back into the swing of writing my stories, so the reviews I get will factor into that which I update first. So be sure to review!

PS: While I am taking down chapter three to write the second half to it, those of you who have already read it can consider it a sneak peek.

* * *

 **RazenshiaSapphire1306:** Yeah, the seal was slightly based off of Pandora Heart's contractor seal because some of the markings could blend easily into flame. And I even have a fun little fact. Since Satan is immortal, he mainly uses his heirs during breaks. So every hundred years or so depending on how he is feeling, he will have one of his children take a turn ruling Hell. Last time it was the Ninth Heir's turn, so this next upcoming time it is the Tenth Heir's turn.

 **IAsajsd:** Gokudera will be formally introduced likely within the first few chapters. After all, even if Tsuna says it is okay, he can't just sit back and trust a human to look after his Juudaime.

 **SilverWhiteDragon:** I'll see how the story goes. Though Gokudera really does remind me of a little kid picking on the person he secretly loves.

 **RazenshiaSapphire1306:** Well you'll just have to keep reading. And no problem. I start school in roughly ten days so I am going to keep on updating frequently while I have the time. Once school starts, it will likely slow down.

 **X3:** The Guardians will show up when they run out of patience. Since Tsuna, their King, is in the human world and they have a contract of sorts between demons to look after him they can follow him. I will likely explain in more depth later when they come in.

 **Sakura:** Yes. I may hit a point where he goes by Tsuna, but at the moment he goes by Mercy. It is short for his real name, which can be translated into Tsunayoshi in japanese.

 **Lil' Doormouse:** Thank you. Yes I've read that one and a few others. Part of my interest in the supernatural fics like that sparked my desire to write this.

 **Random Reviewer:** He is laid-back for the most part, but he is still Tsuna. He will spazz out when freaking out. While it takes more to get him to freak out, it is less likely. He does pout a lot though instead of scream.

 **Luce Giglo Nero:** Demons, while having preferred genders and birth genders are all genderfluid up to a point. Tsuna could appear as a human male or female, as could the others. So yes there may be some cross-dressing. And Skull is a half-demon. Viper/Mammon is in fact Mammon or the personification of the Sin of Greed. He just likes to troll people and play human/hunter because he can get more money that way.

 **SparrowKyo:** Daemonium Pacisor Mercy means Demon (to) Contract Mercy. And Tsuna would likely get into the mafia to help his brother Giotto, who ended up possessing Dino and is using him and his famiglia to try and take out some of the darker parts that Vindicare itself doesn't touch. Things like human trafficking and such.

 **Guest:** Here is the update my friend.


	3. Lapse 2

**Lapse 2**

* * *

" _Desperate times call for desperate measures. And when desperation hits sometimes the most dangerous of decisions are made."_

* * *

 _-47 years ago-_

The building was dark. Not even the faint light from the moon and the outside lights could pierce the thick miasma that decided to take residence there in the abandoned amusement park. Each step echoed in among the hallways only to get swallowed in the cracks that stood out in the walls.

"How sad," Mercy couldn't help but comment as his eyes supplied both what the building once was and that of its current state. The two images sat in front of his eyes, the currently overlaying the sepia duplicate of the past. "To think humans would desert such a place with such soul and leave it for the elements and otherworldly to claim it."

Every presence of every person to have stepped into the building left faint impressions and vibrations of energy. If enough were to amass inside the walls that absorbed them, then the location would gain a soul of its own. It was the most common cause of supposed hauntings, rather than simply a vengeful human spirit, though that occurred on occasion.

Mercy, like Giotto, could sense those souls. But this one was also tainted by an outside source. A particularly hostile human caught in the web of a slow death but being too negative to simply lay down and pass on. So instead he was turning into a demon.

While such jobs could usually be left to hunters, they were an unreliable bunch. They only really took jobs that other humans gave, and even then it was because they would get paid. As grand and holy as some hunters tried to make themselves off to be, they were no different than any other human. If anything some were worse, refusing help if the pay wasn't to their standards. This was one such case.

Mercy normally wouldn't get involved, but he knew this human personally. It had been his land that the human ended up during his visit to Hell courtesy of the humans experimenting on him. While Mercy couldn't actively help, he was able to help to some degree. But now that the man was free and left festering in his pain, the young demon thought it only right he come personally.

"Mukuro!" he began to call out as the miasma thickened to an almost suffocating level. Or at least it would have done such to a human. For Mercy, it felt like walking through a refreshing shower. Proof enough that no matter how decent a being he was or attempted to be, he would always be a demon at the core. A creature that revelled in darkness. But such depressing laments of his existence were better saved for later.

"Mukuro!"

"My my, does my ears deceive me? Did a king of hell really come to comfort little old me?"

The voice that chuckled from down the hall would have sent a lesser soul shivering. Mercy though wasn't as weak as his human form suggested and he prided himself on his observant nature. From that he could catch the slightest tones of sorrow dripping in the other's tone.

Without even pausing to gather himself, the demon rounded the corner and came face to face with the more cloying of scents. Blood and illness lingered on the air, making his face scrunch as the taste of aged copper hit his sensitive tongue catching the air.*

Golden eyes locked on the two bodies that laid across the floor at Mukuro's feet, said man's back leaned roughly against the back of the sofa. Upon closer inspection, it became obvious that their deaths were the cause of their bodies giving out slowly thanks to the many experiments done to them. And, despite Mukuro's faint laughter, the wet spots around the collar of his shirt suggested he was mourning the deaths of his friends.

"Why Mercy. So nice to see you again. I would stand and welcome you to my humble abode, but as you can tell I'm not exactly in the best of health for that,"

"I know what's going on and so do you,"

"Oh? And what do I obviously know?"

"That you are becoming a demon," At those words, the purple haired man's heterochromatic eyes sharpened, locking onto Mercy's own vibrant orange and searching for any sign of a lie. Once he got his fill of the truth that radiated from those unnatural orbs, he slumped back.

"I am, huh? I wonder why just me though,"

"You wish your friends were coming with you,"

Mukuro immediately opened his mouth to deny it only to close his mouth a moment later, as if suddenly changing his mind.

"I guess there is no point in me lying to you. Kufufufaahh.** We finally got free only for them to turn around and die not even a few days later. Fate is truly unkind to those it hates,"

"If you like I can revive them…" Mercy mumbled lightly, unable to bear the psychotic but rarely melancholy man look as though he lost all the fight in him.

In return, Mukuro's eyes flashed for a moment.

"They'll be demons though… as a high rank demon, if their souls are still in limbo I can contract them to serve me, effectively making them demons… But they could never regain their humanity.."

"KUFUFUFUFUHAHA! Mercy-dear, you shouldn't say that like it is a bad thing. In my time among your kind, while cruel, their cruelty did little to surpass that of humanity," Mukuro moved to wipe the tears that spilled from his eye at the sudden bout of laughter, "Now then, if you will revive my friends we can now leave this hellhole. The sooner we are free from Earth, the sooner I can start my new life as your guardian,"

 _-Present Day-_

The building was much like the one all those years ago, but replacing those battered walls of stone were ones of plaster whose white paint still gleamed freshly. The carpet underfoot was firm, but of a rich dark beige color.

At Mercy's side Reborn walked with a brisk pace, eyes only locked ahead and gun out fisted in his fingers. Like all those years ago, the demon could also see the echoes, by they chose to hug the floors alone thrumming like a photo taken in motion. According to the report he spotted over the hitman/hunter's shoulder, this building has been abandoned for many years before someone decided to buy the property and gut it. Only the skeleton of the original building was left untouched in all the work.

But, unknown to Reborn was the deep seated darkness that seemed to permeate the structure. It was obvious this place had happily been adopted by some of the free demon population and made as their home for quite some time. Part of Mercy couldn't help but feel bad for the demons who were forced into a frenzy as humans marched in and claimed their home.

" _Humans are the worst kind of parasites in this world. They leach from it without a single thought for any other life or creature besides themselves,"_ The familiar words of Mukuro thrummed in his memory as Mercy recalled the man who was human only in species. His own kind made sure to stamp all over whatever humanity he may have had before.

"OI, IDIOTA MERCY!"

[Pause! Below is a very colorful phrase courtesy of a demon who had his ear screamed in. For anyone sensitive to coarse language, you have been warned.. (Also I don't want anyone getting pissy about the use of deggo. It was only used as an insult by a pissed off demon so please don't flame me for using it)]

"What the fuck you cockass motherfucked!? That was my goddamn ear!? I know you think you are a bad-ass deggo, but for fucks sake, screaming in the ear of a being whose hearing is more sensitive than yours*** is a dick move!" Mercy screeched as he clapped his hands over his ringing ears. He was distantly aware of Reborn staring at him with wide eyed but he didn't care. That freaking hurt.

Sadly he wasn't able to mourn his ear for much longer as a nearby wall decided to pick that time to be smashed open by a few pissed off demons.

"This may be the time to name me…"

With a crash, Reborn immediately went on guard, his eyes roving distantly over the pathetically useless demon. Said demon was spouting crap about names. And, while Reborn knew next to everything about demons and how they worked, he himself had not had any personal experience in summoning. But he was pretty sure things such as that weren't necessary.

"Just stay behind me if you can't find," Utter the raven with a huff as his fingers snatched the small wrist and pulled. The movement was right in the nick of time as the demons that came through the wall picked that moment to burst through.

Holy-water filled rounds dispersed the shadows, but for every part that withdrew another came for. The twisting mass of demons that were beginning to join together let out unholy shriek after shriek as they were hurt. Yet all it simply did was spurn their anger.

"Reborn! You have to name me and finish the contract! This is beyond you!" Mercy called out from his place behind the hunter. The high soprano of his yells and the words themselves prompted the narrowing of Reborn's dark eyes in annoyance.

"Tch. You are a pretty pathetic demon aren't you? If I am so overmatched, why don't I just throw you into them and let them have your way with you while I run instead?"

"R-Reborn… I-I… uh... I didn't mean it that way, Idiot-Hunter. If you weren't so arrogant you would see that no matter how skilled you are there is no getting over the disadvantage you set for yourself. You are simply not equipped to handle this many demons. The reports dissuaded you into not packing heavy for this job and while I know you keep spares in your car, you are in no place to be able to go get them," As Mercy spoke, his tone became darker and more sly. Each word the panic and almost pathetic attitude that started his words melted away into the calmness born of experience. That in and of itself caused Reborn to turn his onyx eyes onto the young demon.

"So then what do you suggest, Pathetic-Mercy?"

"I suggest you do what I said earlier and finish the contract with a name,"

Now that repeat of the name thing left Reborn slightly at a loss. If it was used again, it must be important. But sadly, he would have to learn this now while fighting off a surging mass of combined demons.

"Okay speak. How is it relevant and how do I do it?" Another round of shots went off as Reborn shifted his position, one eye fixed on the demon behind him and silently prompting the individual to explain.

"Well it completes the contract by giving the power a special word or name to use to prompt the activation of the contract. Each name manifests the demons power in a different way. You didn't pick one, so my power is sealed as part of a safety device made to keep other demons from trying to kill their contractor before the contract is completely set,"

Now Reborn wasn't an easily impressed individual, but the speed at which the demon explained why still keeping it understandable earned his praise. But soon his mind was brought back to the mass of demons, his gun clicking to signal the end of the clip. His lips thinned and his expression soured as he found himself backed into a corner. The gun was sent flying at the mass as he drew another from his coat.

"So I just have to pick a name right?"

"I guess? I don't know how the naming system really works,"

The hitman snorted at that, before adding darkly, "Not very useful know aren't you?"

"Well why should a demon know how humans pick names for our kind anyway?" The young demon was quick to call Reborn out, his expression only really able to be explained as a pout as he stepped back in tangent with Reborn's own movement.

"Fine. Let's see, what names do I know off the top of my head…" Another clip was emptied into the creature, only giving him a minute to think as he reloaded and took aim back at the shifting dark shadow that was slowing but not stopping.

"Just pick one,"

"Fine. Tsunayoshi. There,"

Well that name, spoke in the most uninterested tone did the trick. Though it did bring a wrinkle to the nose of the demon.

"Why that name?"

"You look Japanese and my last boss had a particular fascination with Tokugawa Shoguns. I could have always picked a girl's name,"

[Wow Reborn. You made that so anti-climatic.]

"Okay, well whatever works," Mercy, or Tsuna, responded to Reborn's words with a grin that wasn't exactly pure as he touched the blazing orange contract that came to life on his collarbone, "What's your order's boss?"

Reborn twisted to stare at the demon.

"What do you think they would be? Maybe destroy the demon,"

"You're no fun,"

"I'm going to shoot you…"

"Fine," Tsuna spread his arms, twisted orange magic glowing upon his fingertips as he uttered a few words in a language that wasn't exactly human.

" _Exite custos grandinem venti tempestatis in fine._

 _Red quasi lux caeli flammis coruscantes metus deorsum._

 _Creaturarum, sanctus dicetur, non plenarie malevolentia._

 _Manus in manu imbre consurgens._

 _Alium autem tutorem qui de caelo._

 _Flammam hyacintho._

 _In momento et venite ad me._

 _Nominis invocarem nomina data._

 _Turbine et a pluvia._

 _Gokudera, Yamamoto, Conjuro te." ****_

The orange flames touched the ground and ignited as Tsuna directed his hands below him. From that a portal of swirling gold appeared, only to sprout from it two flames. One of red, the other of blue.

Amidst those two flames materialized two boys who looked roughly like human teenagers, save for the more demonic additions. A japanese boy with eyes of flinted gold and black forked horns like those of a chinese dragon tipped in a velvet-like covering. A tail much like a dog hung free from his clothes while his ears edges were serated in a feather-like fashion.

The other had hair of an unnatural silver, eyes a luminescent green whose pupil was slitted. Ears and two tails of a cat decided to act as his inhuman features. Yet both were smiling faintly as their eyes flickered toward the demon behind him.

"You ready, Sword Freak?" The silver boy asked his partner, his own hands lined with explosives.

"Yes. Let's go,"

And the two with synchronised movements charged forward.

 **Omake! Demonology with Mercy!**

Mercy settles on the desk with his legs crossed.

"Okay today we will be covering names in anticipation of the next chapter.

"Demons by nature are fluid creatures in many aspected. Race, gender, and appearance are constantly changing for demons. While some prefer one over the others, they have to be prepared to change it after a moment's notice. This has to do with names.

"Each time a demon is contracted by a human, they gain a new name. While they may be required to introduce themselves to some extent, these pet names are usually replaced by a name chosen by the contractor. This name both acts to bind the demon to them and unlock their power while simultaneously shaping it. Think of it this way. A demon's power is like electricity and a name is like a wire used to direct and control the electricity, giving it a function.

"For each name a demon has a different form born from the release of their powers while also gaining so strength from their connection to the human. It is next to unheard of for a demon to have the same form for different names, but they may have similar aspects. In fact there is one aspect that will stick with a demon no matter what their form or name may be. This aspect acts as an identifier.

"Now, despite their fluid nature, demons do in fact have a true form. That true form is under their true name. It is said if a human gets ahold of a demon's true name, they can have next to an unbelievable amount of control over that demon. It comes from the fact that the human is then tied to the core of the demon itself rather than the individual chunk of power categorized under a name.

"Keeping with the electricity theory, instead of possessing the simple appliance or set of appliances, the human has control of the entire power station.

"So once I receive a name from Reborn, I will have more access to my abilities but he will also have more control over me. A double-edged sword if you will.

"Anyway that is all. Thank you for having me."

* * *

 ***** Mercy's tongue is structured much like a snake's, allowing enhanced sense of smell when he "tastes" the air. He usually only uses this though when tracking.

**For anyone who is confused it is a mixture of his signature laugh "Kufufufu" and "Haahh" which is the sound made when you sign.

***Roughly as sensitive as a dogs.

**** Come forth in the throes of wind and hail my guardian of Storm.

Like a flash of red decorating the flames of the sky that blaze beneath.

Of the creatures not holy nor of complete malevolence.

Hand in hand, you rise with the rain.

Another guardian who speaks of the sky.

A flame of blue.

Both in a flash, come to me.

Your names I call, names I granted.

Storm and Rain.

Gokudera, Yamamoto, I summon thee.

* * *

 **Razenshia:** Well you will see their reaction eventually. And yes, I had fun writing that bit. He himself won't fight until he really has to. But when he does, it should be pretty good and definite truth that he is high ranked.

As for pairings, there probably will be. I can write any of them save for G27 just simply because that one has always be a little strange to me... I may in the end make a poll or something, but that will start after the introductory arc.

 **X3:** You will see how Nagi works when I get into the first story arc. But Chrome will definitely be there. I can't leave poor Chrome out.

 **Sakura:** It will pick up even more and hopefully my writing will improve once I get past the tedious introductory arc.

 **CatunaCaty:** Gracias. Lo siento por los errores. Tuve que usar traductor Google. No hablo español. Solamente inglés, francés básico, y algunas japonés. ^. ^ "

 **luwiluwi:** Thank you. And it really depends on you people. Even if this one isn't completely finished, I am plotting out a really long detailed one I plan on making that will likely be completed no matter what. I am just waiting until everything is set up and also planning on searching for a beta for it. If you know anyone interested...

 **sarahgri99:** Yeah it hurt. To him it was probably like being given tetanus shots all over his body. But they didn't kill him. To kill a high level demon like him, you would definitely need more than bullets. Both things are explained to some degree in this chapter's omake, namely the second. But some things can be taken for the first.

 **Foxluna:** Well now he has Yamamoto and Gokudera, so I'm pretty sure some of that will end. But even if it doesn't, I think Reborn will be in for something bad if he keeps it up and managed to finally piss off Tsuna.

* * *

Author Note!:

I apologize for any crappiness in this writing. I know I am not the best, but I keep on trying. I am still a little rusty in certain aspects, but hopefully it will get better as I keep going.

But at any rate I got this far. In the background I have been working on a better version of this same idea. For that one it will be slow going and none of the chapters will be posted unless I am 100% pleased with it, but don't worry. Even if I do start getting more ground with the other, I will keep this one up for those who enjoy it.

Anyway remember that I feed on reviews. So review and I will see you next time!


	4. NOTE!

Okay I am busy with school, possibly work soon, and two rp sites. But that doesn't give me the excuse of not updating at least once a month. For that I apologize. I am finally back into writing frequently. It may be slow at first, but I want to set myself up to at least update two stories a month. If nothing else, two 2,000+ word chapters I should be able to manage considering I can fabricate multiple 500 word posts in a day.

With that said, I may not do the same stories or update it like clockwork. But unless I set myself up to update two, I will procrastinate. I know this about myself. I am bad for it.

So for those who are curious, here is my update list:

 **Midas** \- To live or to die. Everyone has a desire to live, but sometimes it would be better to simply remain dead. It is often said that the greatest gifts have the worst of prices. To live or to be alive, the double-edged sword of humanity. As fickle as immortality's rank as a gift or a curse. One thing is for sure... gifts, while freely given, aren't always freely received. Pride!Ed

 **Choice and Consequence** \- When Almedha realizes her child is pure Laguz and not Branded, her mistakes come back to bite her. By making a deal with the devil (Izuka) she manages to hide the child's true power, but it only caused more problems for the assumed Branded. Now Soren has all but hit his peak of growth and the time comes for him to learn the truth. Where will it leave him?

 **The Fate of Shadows** \- Rajaion is dead. Ashnard escaped at the last minute. Amid the mercenaries he recognized someone that he never expected to see again. New plans are made and all is seemingly lost. Can the heroes escape this turn of events when one of the enemies is a twisted shell of their irreplaceable tactician? Can Ike organize a rescue mission? Or will he be saved by Soren's parting gift?

 **Truth in the Black** \- (A planned re-write of my most popular story, the True Bloodstained Black Rabbit)

For those not on the list, I have a little something else planned...

 **Phantom Orange** is going to be taken down and possible editted/replaced. It will be worked on and hopefully be finished in time for Halloween.

 **Daemonium Pacisor Mercy** is going to be absorbed into a story I have been plotting out for a while. It follows the similar idea of demons and summoning, but it is a different take on it.

 **Only Noise** was an attempt that got swallowed up into nothingness. It will likely not be updated.

 **Seven Seconds** has been thrown onto the back burner until further notice and may join Daemonium Pacisor Mercy on the revamp stage depending on my mood/muse.

 **Arc of Nothings** was a strange story inspired by an even stranger dream and I honestly can say I don't see it going anywhere.

 **The Heart of Pandora's Wonderland** was a surreal take on the story that I will likely shove into the corner as most of it came to me when I was in a very strange mental state.

I also plan on eventually investing in writing my first crossover story, I just have to wait until I get into this set-up more. Anyway, for those of you who have been wondering if/when things will get done this is for you. I wish I could tell you something more concrete, but it will really vary on the month. For this month at least I will start on my re-write and add another chapter to Midas. But other than that, all I can tell you is to keep an eye out!

Thank you for your time.

-With Luffles, Aureux


	5. Update!

I am fixing up the ideas surrounding this story, edit it, giving it a concrete plot, and re-releasing it. With hopes, those of you still holding interest will be delighted.

I really don't know much what else to say other than what I types above, so with luck, Aureux.


End file.
